Technological Field
The present invention relates to an image forming apparatus.
Description of the Related Art
Conventionally, in an electrophotographic image forming apparatus, toner scatters in the apparatus and ozone is generated, and thus a mechanism to recover the toner and the ozone is provided.
For example, as illustrated in FIG. 10, ozone G is generated when a photosensitive drum 81 is charged by a charger 82, and scattered toner (hereinafter, simply referred to as toner) T is generated when a toner image is formed on the photosensitive drum 81 by a developer 83. Therefore, an image forming apparatus (hereinafter, referred to as conventional configuration A) is used in which a toner filter 84 and an ozone filter 85 are provided in series and a common suction fan 86 is used to suck the toner T and the ozone G in the same path (see JP 8-220952 A).
In addition, with realization of multi-color and high-speed of the image forming apparatus, improvement of suction performance for the toner and ozone is required, and thus securing of a wind speed for sucking both the toner and ozone is difficult with a single suction fan. Therefore, as illustrated in FIG. 11, a configuration (hereinafter, referred to as conventional configuration B) is employed in which functions to suck the toner T and to suck the ozone G are separated. In the conventional configuration B, toner T generated when a toner image is formed on a photosensitive drum 91 by a developer 93 is recovered using a toner filter 94 and a toner suction fan 95, and ozone G generated when the photosensitive drum 91 is charged by a charger 92 is recovered using an ozone filter 96 and an ozone suction fan 97.
However, in the conventional configuration A illustrated in FIG. 10, the suction path of the toner T and the suction path of the ozone G join upstream of the toner filter 84. Therefore, there is a problem that, when the toner filter 84 is clogged, the suction wind speed is decreased, and both the toner T and the ozone G cannot be sucked. In a case where the toner filter 84 and the ozone filter 85 are integrally formed, the whole filter is replaced in accordance with the filter having a shorter lifetime, and thus the filter having a longer lifetime cannot be used up. Further, when toner adheres to the ozone filter 85, oxidized odor may be generated, and thus there are design restrictions such as disposing the toner filter 84 on the upstream side.
Further, in the conventional configuration B illustrated in FIG. 11, the suction of the toner T and the suction of the ozone G are performed in different paths, but since a region where the toner T is generated and a region where the ozone G is generated are close to each other, there is a problem that the ozone G is sucked at the time of sucking the toner T. Since particles of the toner T are larger in mass than the ozone G, force to suck the toner T is stronger, and the ozone G is easily mixed in the toner suction path side. The mixed ozone G is discharged to an outside of the apparatus without passing through the ozone filter 96.